Regular Polyhedra
A polyhedron is a three-dimensional (3D) shape with flat faces.
A regular polyhedron has:
- Faces that are identical regular polygons
- the same number of faces meet at each vertex (corner)
Otherwise it is irregular.
Regular icosahedron
(20 identical faces,
all equilateral triangles)
Irregular icosahedron
Platonic Solids
The 5 Platonic Solids are all regular polyhedra
